r - 如何增加ggplot2中分组条之间的空间？

Question

[数据和代码在帖子末尾生成情节]

使用 ggplot，我绘制了一个带有误差线的条形图，条形图按两个因素分组(一个在 X 轴上，一个用填充)。 我想增加 xaxis 上组之间的绿色距离 使情节更易于阅读:


我发现最接近 stackoverflow 上的解决方案 here (有人在未回答的评论中问了我的问题)，here , here ，但我没有设法在不累积误差线的情况下应用这些。有人可以指出我要调整的正确参数吗？

数据:

structure(list(Condition = c("Difficult", "Easy", "Difficult", 
"Easy", "Difficult", "Easy", "Difficult", "Easy", "Easy", "Difficult", 
"Easy", "Difficult"), Measure = c("Competence", "Competence", 
"Value", "Value", "Interest", "Interest", "JOL", "JOL", "Difficulty", 
"Difficulty", "Effort", "Effort"), mean = c(5.5, 4.72, 4.04, 
5.39, 3.51, 3.77, 4.34, 4.61, 3.51, 1.51, 3.44, 1.73), sd = c(1.26, 
1.62, 1.94, 1.34, 1.46, 1.46, 1.73, 1.68, 1.5, 0.86, 1.53, 1.1
), se = c(0.14, 0.18, 0.22, 0.15, 0.16, 0.16, 0.19, 0.19, 0.17, 
0.1, 0.17, 0.12), s.size = c(80, 80, 80, 80, 80, 80, 80, 80, 
80, 80, 80, 80)), .Names = c("Condition", "Measure", "mean", 
"sd", "se", "s.size"), row.names = c(NA, -12L), class = "data.frame")

即:

   Condition    Measure mean   sd   se s.size
1  Difficult Competence 5.50 1.26 0.14     80
2       Easy Competence 4.72 1.62 0.18     80
3  Difficult      Value 4.04 1.94 0.22     80
4       Easy      Value 5.39 1.34 0.15     80
5  Difficult   Interest 3.51 1.46 0.16     80
6       Easy   Interest 3.77 1.46 0.16     80
7  Difficult        JOL 4.34 1.73 0.19     80
8       Easy        JOL 4.61 1.68 0.19     80
9       Easy Difficulty 3.51 1.50 0.17     80
10 Difficult Difficulty 1.51 0.86 0.10     80
11      Easy     Effort 3.44 1.53 0.17     80
12 Difficult     Effort 1.73 1.10 0.12     80

我用来制作绘图的代码(请原谅评论，我正在学习如何使用 ggplot 并发现做笔记很有帮助)

library(ggplot2)
ggplot(DF, aes(x=Measure, y=mean,fill=Condition)) + 
  geom_bar(stat="identity",
           colour="black",    # Black outline for all
           position=position_dodge())+# Put bars side-by-side instead of stacked
  geom_errorbar(aes(ymin=mean-se, ymax=mean+se),
                position=position_dodge(.9), 
                width=.25)+
  #order the groups on the xaxis
  scale_x_discrete(limits = c("Interest", "Value","Effort","Difficulty","Competence","JOL"))+
  coord_cartesian(ylim=c(0,7)) +
  #change color of bars
  scale_fill_manual(values=c("#ffcc00ff","#ffffff"), name = "Condition") + 
  #change ticks on yaxis
  scale_y_continuous(breaks=seq(0,7,by =1)) + 
  geom_hline(yintercept=0) +
  geom_vline(xintercept=0)+
  theme_bw()+
  labs(x="", y = "Rating (0-7)")+
  theme(axis.line.y = element_line(color="black"),
        axis.title.y = element_text(margin = margin(r=8)),
        axis.title.x = element_text(margin = margin(r=25)),
        panel.background = element_rect(fill = NA),
        panel.grid.major = element_blank(),
        panel.border = element_blank())

Answer 1

什么事？
1.使用geom_col而不是 geom_bar如推荐。
2.指定合适的position_dodge(0.5)和 width=0.5和 3. 删除不必要的代码。

ggplot(d, aes(x=Measure, y=mean, fill=Condition)) + 
  geom_col(colour="black",width=0.5,    
           position=position_dodge(0.5)) +
  geom_errorbar(aes(ymin=mean-se, ymax=mean+se),
                position=position_dodge(0.5), width=.25)+
  scale_x_discrete(limits = c("Interest", "Value","Effort","Difficulty","Competence","JOL")) +
  scale_y_continuous(breaks=seq(0,7,by =1),limits = c(0,7), expand = c(0,0))+
  scale_fill_manual(values=c("#ffcc00ff","#ffffff"), name = "Condition") + 
  labs(x="", y = "Rating (0-7)")+
  theme_minimal() +
  theme(axis.line = element_line(color="black"),
        axis.ticks = element_line(color="black"),
        panel.border = element_blank())